1. Technical Field
The present invention relates to a printing apparatus that performs maintenance of an ink discharge head, and a maintenance method for a printing apparatus.
2. Related Art
In the related art, there has been known a printer that includes a print head for discharging ink, a wiper for wiping the print head, a tank that stores the ink to be supplied to the print head, and an ink circulation mechanism that circulates the ink between the tank and the print head. This printer performs pressure cleaning of the print head in which the printer increases the ink circulation speed to a speed faster than that in print operation, applies a pressure to the ink to discharge the ink from a nozzle of the print head, and then, in a state where the pressure application to the ink is stopped, wipes the print head with the wiper (see, for example JP-A-2014-172238).
The inventor has found the following problems. Known printing apparatuses such as printers increase an ink circulation speed in wiping operation to a speed higher than that in print operation to increase a back pressure in an ink discharge head (hereinafter, referred to as “head back pressure”) in the wiping operation to be higher than a head back pressure in the print operation so as to prevent, for example, bubbles from entering the inside of the ink discharge head from the nozzle. If the ink is circulated in the wiping operation, however, it is difficult to control the head back pressure to remain within a desired range because the ink pressure loss in the ink circulation flow path varies along with variation in ink viscosity.